The influence of acceleration and deceleration on shock wave movement on and around aerofoils in transonic flight |
| |
Authors: | Hamed Roohani B W Skews |
| |
Institution: | (1) University of the Witwatersrand, PO Wits, Johannesburg, 2050, South Africa |
| |
Abstract: | This paper examines the shock wave dynamics of a biconvex aerofoil in transonic flight during acceleration and retardation.
The aerofoil has a cord length of 1 m and air at infinity is at 101.325 kPa and 300 K. Using Fluent as the CFD software, constant
velocity (steady state) simulations were conducted at transonic Mach numbers. The aerofoil was then accelerated at 1041m/s2 (106 g), starting at Mach 0.1, and decelerated at −1041m/s2, starting at Mach 1.6, through the same range of Mach numbers using time-dependent (unsteady) simulations. Significant differences
were found in the transonic region between the steady and the unsteady aerodynamic forces. Analysis of the flow field in this
region showed that acceleration-dependent variations in the position of the shock wave on the surfaces of the aerofoil were
the main reason for this. As very high accelerations were used in order to emphasize differences, which do not have many practical
applications, simulations using accelerations lower than 9 g were also conducted in order to confirm the results. The acceleration-dependent
behaviour of other shock waves around the aerofoil, such as the bow shock in front of the aerofoil and the trailing wave were
also examined. The trailing wave followed behind the aerofoil changing position with different accelerations at the same Mach
number.
|
| |
Keywords: | Acceleration Transonic Shock |
本文献已被 SpringerLink 等数据库收录! |
|